package upicgame.utils;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Random;

/**
 * @program: upicgame
 * @description: 生成验证码工具类
 * @author: lhq
 * @create: 2019-12-24 11:49
 */
public class VerifyCode {
	private int w = 70;
	private int h = 35;
	private Random r = new Random();
	// {"宋体", "华文楷体", "黑体", "华文新魏", "华文隶书", "微软雅黑", "楷体_GB2312"}
	private String[] fontNames  = {"宋体", "华文楷体", "黑体", "微软雅黑", "楷体_GB2312"};
	// 可选字符
	private String codes  = "0123456789abcdefghjkmnopqrstuvwxyzABCDEFGHJKMNPQRSTUVWXYZ";
	// 背景色
	private Color bgColor  = new Color(255, 255, 255);
	// 验证码上的文本
	private String text ;

	// 生成随机的颜色
	private Color randomColor () {
		int red = r.nextInt(150);
		int green = r.nextInt(150);
		int blue = r.nextInt(150);
		return new Color(red, green, blue);
	}

	// 生成随机的字体
	private Font randomFont () {
		int index = r.nextInt(fontNames.length);
		String fontName = fontNames[index];
		//生成随机的字体名称
		int style = r.nextInt(4);
		//生成随机的样式, 0(无样式), 1(粗体), 2(斜体), 3(粗体+斜体)
		int size = r.nextInt(5) + 24;
		//生成随机字号, 24 ~ 28
		return new Font(fontName, style, size);
	}

	// 画干扰线
	private void drawLine (BufferedImage image) {
		int num  = 3;
		//一共画3条
		Graphics2D g2 = (Graphics2D)image.getGraphics();
		for(int i = 0; i < num; i++) {
			//生成两个点的坐标，即4个值
			int x1 = r.nextInt(w);
			int y1 = r.nextInt(h);
			int x2 = r.nextInt(w);
			int y2 = r.nextInt(h);
			g2.setStroke(new BasicStroke(1.5F));
			g2.setColor(Color.BLUE);
			//干扰线是蓝色
			g2.drawLine(x1, y1, x2, y2);
			//画线
		}
	}

	// 随机生成一个字符
	private char randomChar () {
		int index = r.nextInt(codes.length());
		return codes.charAt(index);
	}

	// 创建BufferedImage
	private BufferedImage createImage () {
		BufferedImage image = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
		Graphics2D g2 = (Graphics2D)image.getGraphics();
		g2.setColor(this.bgColor);
		g2.fillRect(0, 0, w, h);
		return image;
	}

	// 调用这个方法得到验证码
	public BufferedImage getImage () {
		BufferedImage image = createImage();
		//创建图片缓冲区
		Graphics2D g2 = (Graphics2D)image.getGraphics();
		//得到绘制环境
		StringBuilder sb = new StringBuilder();
		//用来装载生成的验证码文本
		// 向图片中画4个字符
		for(int i = 0; i < 4; i++)  {
			//循环四次，每次生成一个字符
			String s = randomChar() + "";
			//随机生成一个字母
			sb.append(s);
			//把字母添加到sb中
			float x = i * 1.0F * w / 4;
			//设置当前字符的x轴坐标
			g2.setFont(randomFont());
			//设置随机字体
			g2.setColor(randomColor());
			//设置随机颜色
			g2.drawString(s, x, h-5);
			//画图
		}
		this.text = sb.toString();
		//把生成的字符串赋给了this.text
		drawLine(image);
		//添加干扰线
		return image;
	}

	// 返回验证码图片上的文本
	public String getText () {
		return text;
	}

	// 保存图片到指定的输出流
	public static void output (BufferedImage image, OutputStream out) throws IOException {
		ImageIO.write(image, "JPEG", out);
	}
}
